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<b>DB_ENV-&gt;log_file</b>
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<tt>
<b><pre>
#include &lt;db.h&gt;
<p>
int
DB_ENV-&gt;log_file(DB_ENV *env,
    const DB_LSN *lsn, char *namep, size_t len);
</pre></b>
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<b>Description: DB_ENV-&gt;log_file</b>
<p>The DB_ENV-&gt;log_file method maps
DB_LSN structures
to filenames, returning the name of the file containing the record named
by <b>lsn</b>.</p>
<p>This mapping of
DB_LSN structures
to files is needed for database administration.  For example, a
transaction manager typically records the earliest <a href="../api_c/lsn_class.html">DB_LSN</a> needed
for restart, and the database administrator may want to archive log
files to tape when they contain only <a href="../api_c/lsn_class.html">DB_LSN</a> entries before the
earliest one needed for restart.</p>
<p>The DB_ENV-&gt;log_file method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>lsn</b><ul compact><li>The <b>lsn</b> parameter is the
DB_LSN structure
for which a filename is wanted.</ul>
 <b>namep</b><ul compact><li>The <b>namep</b> parameter references memory into which
 the name of the file containing the record named by <b>lsn</b> is copied.</ul> 
 <b>len</b><ul compact><li>The <b>len</b> parameter is the length of the <b>namep</b> buffer in
bytes.  If <b>namep</b> is too short to hold the filename,
DB_ENV-&gt;log_file will fail.  (Log filenames are normally quite short,
on the order of 10 characters.)</ul>
<br>
<br><b>Errors</b>
<p>The DB_ENV-&gt;log_file method
may fail and return one of the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If supplied buffer was too small to hold the log filename; or if an
invalid flag value or parameter was specified.</ul>
<br>
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<br><b>Class</b>
<a href="../api_c/env_class.html">DB_ENV</a>, <a href="../api_c/logc_class.html">DB_LOGC</a>, <a href="../api_c/lsn_class.html">DB_LSN</a>
<br><b>See Also</b>
<a href="../api_c/log_list.html">Logging Subsystem and Related Methods</a>
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